Magnetic component and power converter using the same

Abstract

To obtain a magnetic component having high heat dissipation properties without reducing functionality.SOLUTION: There is provided a magnetic component including: a magnetic core with an annular portion surrounding window sections; one or more windings wound around the annular portion of the magnetic core; and a cooling plate which is provided passing through the window sections and overlapping the windings, is formed from metal, and cools the windings. The cooling plate has a body section which is a portion overlapping the windings, and a first cooling section and a second cooling section that protrude from the body section. Each of the first cooling section and the second cooling section is at least thermally connected to a cooler. Each of the first cooling section and the second cooling section protrude from respective portions of the body section on both sides of the window sections. A pathway surrounding the magnetic core by way of the body section, the first cooling section, the cooler, and the second cooling section has at least one insulating section, the pathway being electrically insulated by the insulating section.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a magnetic component and a power converter using the same.

Background Art

[0002] Due to recent environmental regulations and technological advancements surrounding automobiles, electrified vehicles such as electric vehicles or hybrid vehicles have been developed and are becoming increasingly popular in various vehicle classes. Electrified vehicles that use a motor as a drive source generally have a plurality of power converters installed. Examples of power converters installed in electrified vehicles include a charger that converts commercial alternating voltage into direct current voltage for charging a high-voltage battery, an inverter that converts the direct current power of the high-voltage battery into alternating current power for the motor, and a DC-DC converter (SDC) that converts the direct current voltage of the high-voltage battery into the direct current voltage of an auxiliary battery (e.g., 12V). Converters such as the above-described charger and SDC have magnetic components such as transformers and reactors installed therein. From the perspectives of securing vehicle space and cost in electrified vehicles, miniaturization and cost reduction of magnetic components and power converters are required.

[0003] A transformer, which is a magnetic component, is a component that transfers the power of a primary winding to a secondary winding by causing the magnetic flux generated by passing a current through the primary winding to link with a current loop formed in the secondary winding. Configurations for miniaturizing and reducing the cost of a transformer have been disclosed (see, for example, Patent Document 1). In the configurations disclosed in Embodiment 1 and Embodiment 2 of Patent Document 1, a heat dissipation plate having a plurality of bent portions is attached to the transformer. The winding and the heat dissipation plate are wound around a magnetic core, and the core heat dissipation plate is arranged parallel to the magnetic core and closest to the magnetic core. The plurality of bent portions are formed by bending a part of the heat dissipation plate. The tip portion of the bent portion is embedded in a potting resin material.

[0004] By configuring in this way, since the heat dissipation plate is arranged in the immediate vicinity of the winding, the heat generated in the winding and the magnetic core is transmitted to the heat dissipation plate. The transmitted heat is dissipated to the potting resin material through the bent portion of the heat dissipation plate, so that the winding and the magnetic core can be miniaturized. Since the winding and the magnetic core are miniaturized, the raw material cost is suppressed, so that the cost of the magnetic component can be reduced.

[0005] In such a configuration, when a fixing portion is arranged at the tip portion of the bent portion and the fixing portion is connected to a metal casing, the heat of the heat dissipation plate can be directly transmitted to the casing. Since the heat of the heat dissipation plate can be directly transmitted to the casing, the heat dissipation characteristics of the transformer can be further improved. The more the number of fixing portions, the more the heat dissipation paths to the casing increase, so that the heat dissipation characteristics of the transformer can be further enhanced.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] In the structure of the transformer of the above Patent Document 1, since a heat dissipation plate is provided, the heat dissipation characteristics of the transformer can be improved. Further, by providing a heat dissipation path to the casing, the heat dissipation characteristics of the transformer can be further enhanced. However, in a transformer having such a structure, a current loop is formed that passes through the heat dissipation plate and the casing and circulates around the leg portion of the magnetic core, separately from the secondary winding. This current loop generates a magnetic flux in the magnetic core. The generated magnetic flux cancels the magnetic flux generated by the primary winding of the transformer, so that a part of the power of the primary winding of the transformer is not transmitted to the secondary winding, and thus the function of the transformer is degraded. In the above-described configuration, there is a problem that it is difficult to improve the heat dissipation characteristics of the transformer without degrading the function of the transformer.

[0008] In addition, the phenomenon that a current loop that circulates through the leg portions of the magnetic core cancels out the magnetic flux in the magnetic core through the heat dissipation plate and the housing described above also occurs similarly even if the magnetic component is a reactor. A reactor is a magnetic component that can have a high L value by passing an electric current through the winding provided in the reactor and generating a magnetic flux in the magnetic core. However, when a current loop that circulates through the leg portions of the magnetic core is generated through the heat dissipation plate and the housing, this current loop cancels out the magnetic flux in the magnetic core in the same way as in a transformer, so the L value decreases, and the function of the reactor deteriorates. In the above-described configuration, there is a problem that it is difficult to improve the heat dissipation characteristics of the reactor without degrading the function of the reactor.

[0009] Therefore, an object of the present disclosure is to obtain a magnetic component having high heat dissipation characteristics and a power converter using the same without degrading the function.

Means for Solving the Problems

[0010] The magnetic component of the present disclosure includes a magnetic core having an annular portion surrounding a window portion, one or more windings wound around the annular portion of the magnetic core, a cooling plate that penetrates the window portion and is provided overlapping the winding and made of metal for cooling the winding. The cooling plate has a main body portion that is a portion overlapping the winding, and a first cooling portion and a second cooling portion protruding from the main body portion. Each of the first cooling portion and the second cooling portion is at least thermally connected to a cooler. Each of the first cooling portion and the second cooling portion protrudes from each of the portions of the main body portion on both sides sandwiching the window portion. The path surrounding the magnetic core by the main body portion, the first cooling portion, the cooler, and the second cooling portion has at least one insulating portion, and the path is electrically insulated by the insulating portion.

Effects of the Invention

[0011] According to the magnetic component of the present disclosure, there are provided a magnetic core having an annular portion surrounding a window portion, one or more windings wound around the annular portion of the magnetic core, a cooling plate made of metal, provided so as to penetrate the window portion and overlap the windings for cooling the windings. The cooling plate has a main body portion which is a portion overlapping the windings, and a first cooling portion and a second cooling portion protruding from the main body portion. Each of the first cooling portion and the second cooling portion is at least thermally connected to a cooler. Each of the first cooling portion and the second cooling portion protrudes from each of the portions of the main body portion on both sides sandwiching the window portion. The path surrounding the magnetic core by the main body portion, the first cooling portion, the cooler, and the second cooling portion has at least one insulating portion, and the path is electrically insulated by the insulating portion. Therefore, the generation of current flowing through the path and magnetic flux caused by the flowing current is suppressed, and the magnetic flux generated by the current flowing through the windings does not decrease. Thus, it is possible to obtain a magnetic component having high heat dissipation characteristics by the cooling plate without degrading the function of the magnetic component, and a power converter using the same.

Brief Description of Drawings

[0012]

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Embodiments for Carrying Out the Invention

[0013] Hereinafter, the magnetic component and the power converter according to the embodiments of the present disclosure will be described with reference to the drawings. In each figure, the same or corresponding members and parts will be denoted by the same reference numerals and described.

[0014] Embodiment 1. FIG. 1 is a perspective view showing an outline of the transformer 1 according to Embodiment 1, FIG. 2 is an exploded perspective view showing the transformer 1, FIG. 3 is a perspective view showing an outline of the magnetic core 12 of the transformer 1, FIG. 4 is a side view of the magnetic core 12 of the transformer 1 as viewed in the Y direction, FIG. 5 is an exploded perspective view showing the coil body 2 of the transformer 1, FIG. 6 is a perspective view showing the primary winding 3 of the transformer 1, FIG. 7 is a perspective view showing the secondary winding 5 of the transformer 1, FIG. 8 is a perspective view showing the insulating plate 4 of the transformer 1, FIG. 9 is a perspective view showing the insulating plate 6 of the transformer 1, FIG. 10 is a perspective view showing the primary winding 3 and the insulating plate 4 of the transformer 1, FIG. 11 is a perspective view showing the secondary winding 5 and the insulating plate 6 of the transformer 1, FIG. 12 is a perspective view showing the cooling plate 7 of the transformer 1, FIG. 13 is a perspective view showing an outline of the power converter 200, FIG. 14 is a plan view showing a main part of the power converter 200 shown in FIG. 13, a view showing the transformer 1 and its surroundings, FIG. 15 is a cross-sectional view of the power converter 200 cut at the A-A cross-sectional position of FIG. 14, a view showing only the part of the magnetic core 12, FIG. 16 is a plan view showing a main part of the power converter 200 shown in FIG. 13, a view showing the cooling plate 7 and its surroundings. The power converter 200 is, for example, a step-down type DC-DC converter that converts the DC voltage of a DC power supply into a secondary-side DC voltage insulated by the transformer 1 and outputs the DC voltage to a load such as a battery. The power converter 200 is not limited to a step-down converter and may be other power converters such as a step-up converter.

[0015] <Configuration of Power Converter 200> An outline of a configuration example of the power converter 200 will be described. The power converter 200 is connected to a DC power supply on the input side and connected to a load such as a low-voltage battery on the output side. The power converter 200 includes an input capacitor that smoothes the input voltage of the inverter circuit, an inverter circuit that has a power semiconductor and converts the input DC voltage into an AC voltage to supply power to the primary winding 3, a transformer 1 that has the primary winding 3 and the secondary winding 5 and converts and outputs the voltage of the AC power output from the inverter circuit, a rectifier circuit that rectifies the AC voltage output from the secondary winding 5, and a smoothing capacitor and a reactor that smooth the output of the rectifier circuit. The transformer 1 and the reactor are magnetic components.

[0016] As shown in FIG. 13, the power converter 200 includes a housing 9 that houses components such as a transformer 1 and serves as a cooler for cooling the components. In FIG. 13, only the transformer 1 and the housing 9 among the components of the power converter 200 are shown, and other components are omitted for simplicity of explanation. The housing 9 is made of a metal such as aluminum, for example. The housing 9 may have a refrigerant flow path through which a refrigerant such as water flows.

[0017] <Transformer 1> The transformer 1, which is a magnetic component, will be described with reference to FIGS. 1 to 12. As shown in FIG. 2, the transformer 1 includes a magnetic core 12 having an annular portion surrounding window portions 12a and 12b, one or more windings (not shown in FIG. 2) wound around the annular portion of the magnetic core 12, and a cooling plate 7 that penetrates the window portions 12a and 12b, is provided on top of the windings, is made of metal, and cools the windings. A closed magnetic circuit, which will be described later, is formed in the annular portion of the magnetic core 12. In the present embodiment, as shown in FIG. 5, the transformer 1 has a plurality of windings, and a coil body 2 having a primary winding 3 and a secondary winding 5, which are the plurality of windings, is formed. Hereinafter, details of each member constituting the transformer 1 will be described.

[0018] First, the magnetic core 12 will be described. As shown in FIG. 3, the magnetic core 12 includes an I-shaped core 10 and an E-shaped core 11. The magnetic core 12 is formed of a magnetic material such as ferrite. The magnetic core 12 has a middle leg portion 11a around which the winding is wound and which extends in the direction of the winding center axis of the winding, outer leg portions 11b and 11c that are spaced apart from the middle leg portion 11a and around which the winding is not wound, and beam portions 10a and 11d that connect the middle leg portion 11a and the outer leg portions 11b and 11c across the winding. The coil body 2 is arranged so as to surround the middle leg portion 11a of the E-shaped core 11. In the present embodiment, the middle leg portion 11a and the outer leg portions 11b and 11c are formed in a rectangular parallelepiped shape. The shapes of the middle leg portion 11a and the outer leg portions 11b and 11 are not limited to this, and may be, for example, cylindrical.

[0019] By abutting the middle leg portion 11a and the outer leg portions 11b, 11c of the E-shaped core 11 against the I-shaped core 10, a magnetic core 12 having two annular portions is formed as shown in FIG. 4. One annular portion is formed by the middle leg portion 11a, the beam portion 10a, the outer leg portion 11b, and the beam portion 11d, and the other annular portion is formed by the middle leg portion 11a, the beam portion 10a, the outer leg portion 11c, and the beam portion 11d. A winding is wound around the middle leg portion 11a that constitutes the annular portion. Closed magnetic paths 101, 102 are provided in each of the annular portions. The closed magnetic paths 101, 102 are the portions indicated by the broken lines in FIG. 4. In the present embodiment, since the magnetic core 12 has two outer leg portions 11b, 11c, the magnetic core 12 has two closed magnetic paths 101, 102. The configuration of the magnetic core 12 is not limited to this, and the magnetic core 12 may have one outer leg portion and the magnetic core 12 may have a configuration having one closed magnetic path. Also, in the present embodiment, the magnetic core 12 is composed of the I-shaped core 10 and the E-shaped core 11, but it is not limited to this. The magnetic core 12 may be composed of two E-shaped cores 11, and the magnetic core 12 may be formed by butting the middle leg portions and the outer leg portions of each of the two E-shaped cores 11.

[0020] As shown in FIG. 2, after passing the central hole 2a provided in the center of the coil body 2 through the middle leg portion 11a, the transformer 1 is formed by abutting the I-shaped core 10 and the E-shaped core 11. Then, by winding the adhesive tape 13 in the longitudinal direction of the magnetic core 12, as shown in FIG. 1, the I-shaped core 10 is fixed to the E-shaped core 11. Here, the directions are defined. The direction of the extended middle leg portion 11a along the winding center axis is defined as the Z direction. The short-side direction of the middle leg portion 11a, which is the direction in which the outer leg portion 11c is provided perpendicular to the Z direction and from the middle leg portion 11a, is defined as the X direction. The longitudinal direction of the middle leg portion 11a, which is the direction perpendicular to the Z direction and the X direction, is defined as the Y direction. In each figure, the direction pointed by each arrow is regarded as one side, and the direction opposite to the direction pointed by each arrow is regarded as the other side. The first outer leg portion 11b is disposed on the other side of the middle leg portion 11a in the X direction, and the second outer leg portion 11c is disposed on one side of the middle leg portion 11a in the X direction.

[0021] FIG. 4 is a view of the magnetic core 12 as seen from the other side in the Y direction. The closed magnetic paths 101 and 102 are the paths through which magnetic flux flows within the magnetic core 12. The closed magnetic path 101 is the path through which magnetic flux flows from the middle leg portion 11a to the outer leg portion 11b, and the closed magnetic path 102 is the path through which magnetic flux flows from the middle leg portion 11a to the outer leg portion 11c. The closed magnetic path 101 is formed surrounding the window portion 12a, and the closed magnetic path 102 is formed surrounding the window portion 12b.

[0022] As shown in FIG. 13, the housing 9 has a cooling surface 9a to which the magnetic core 12 is thermally connected. In the present embodiment, for example, grease having thermal conductivity is applied to the surface on the other side in the Z direction of the E-shaped core 11, and the E-shaped core 11 is thermally connected to the cooling surface 9a. By solidifying the grease, the transformer 1 is fixed to the housing 9.

[0023] Next, the coil body 2 will be described. As shown in FIG. 5, the coil body 2 is arranged by laminating, in order from one side in the Z direction, a cooling plate 7, a secondary winding 5, an insulating plate 6, a primary winding 3, and an insulating plate 4. With a part of the cooling plate 7 exposed, these are covered with the molding resin 8 shown at the upper part of FIG. 5, and thus they are integrated. A gap is provided between the cooling plate 7 and the secondary winding 5, and this gap is filled with the molding resin 8. The molding resin 8 is an insulating resin material such as an epoxy resin. In the present embodiment, as shown in FIG. 2, a part of the cooling plate 7 is exposed, but it is not limited to this. A configuration in which the entire cooling plate 7 is covered with the molding resin 8 may also be acceptable. Even in the configuration where the entire cooling plate 7 is covered with the molding resin 8, the effects of the present disclosure described later can be obtained in the same manner. When a part of the cooling plate 7 is exposed, the heat dissipation characteristics of the cooling plate 7 can be improved.

[0024] As shown in FIG. 5, the primary winding 3 and the secondary winding 5 have through-holes for surrounding the middle leg portion 11a. The primary winding 3 has a central hole 3a as a through-hole, and the secondary winding 5 has a central hole 5a as a through-hole. The windings are formed in a plate shape that is curved on a plane and are wound around the magnetic core 12 in an annular or spiral shape. In the present embodiment, both the primary winding 3 and the secondary winding 5 are provided in a spiral shape and are wound around the magnetic core 12 a plurality of times. Each winding is formed, for example, by punching from a sheet metal such as copper or aluminum using a press die or the like so as to have a predetermined number of turns and winding width. The cross-section of each winding is rectangular. As shown in FIGS. 6 and 7, in the XY plane, a gap is provided between adjacent windings to form a spiral shape.

[0025] The shape of the winding is not limited to a plate shape, and the winding may be in a shape such as a round wire. By forming the winding in a plate shape, unlike the case where the winding is a round wire or the like, the mutually facing surfaces between the primary winding 3 and the secondary winding 5 via the insulating plate 6 and between the secondary winding 5 and the cooling plate 7 can be increased. Since the mutually facing surfaces between the respective windings and between the secondary winding 5 and the cooling plate 7 increase, the thermal resistance between them is reduced, so that the cooling effect of each winding can be improved. Since the cooling effect of each winding is improved, the transformer 1 and the power converter 200 can be miniaturized and cost-reduced.

[0026] In the present embodiment, both the primary winding 3 and the secondary winding 5 are provided in a spiral shape, but the present invention is not limited thereto. One or both of the primary winding 3 and the secondary winding 5 may be provided in an annular shape having a predetermined winding width with a single number of turns and wound around the magnetic core 12. Even if one or both of the primary winding 3 and the secondary winding 5 have an annular shape configuration, the effects of the present disclosure described below can be obtained in the same manner.

[0027] As shown in FIG. 6, the primary winding 3 has a terminal portion 3b at the inner peripheral side end and a terminal portion 3c at the outer peripheral side end. As shown in FIG. 7, the secondary winding 5 has a terminal portion 5b at the inner peripheral side end and a terminal portion 5c at the outer peripheral side end. The terminal portions 3b, 3c and the terminal portions 5b, 5c are formed by bending the ends of the primary winding 3 and the secondary winding 5 at right angles. The terminal portions 3b, 3c and the terminal portions 5b, 5c protrude from the molding resin 8 as shown in FIG. 2. The terminal portions 3b, 3c are connected to the inverter circuit. The terminal portions 5b, 5c are connected to the rectifier circuit.

[0028] In this embodiment, the number of turns of the primary winding 3 is 8 and the number of turns of the secondary winding 5 is 6, but the number of turns of each winding is not limited to this. In this embodiment, the power converter 200 is a step-down DC-DC converter. Therefore, the transformer 1 is configured as a step-down transformer having fewer turns in the secondary winding 5 than in the primary winding 3. In this embodiment, one sheet of each of the primary winding 3 and the secondary winding 5 is provided, but the number of sheets of each of the primary winding 3 and the secondary winding 5 is not limited to this. The primary winding 3 and the secondary winding 5 may be configured by providing a plurality of sheets of each of the primary winding 3 and the secondary winding 5 and connecting the plurality of windings on the inner peripheral side or the outer peripheral side.

[0029] In this embodiment, the transformer 1 having the primary winding 3 and the secondary winding 5 as a plurality of windings is shown as a magnetic component, but the magnetic component is not limited to this. A reactor having a single winding may be a magnetic component. For example, by removing the secondary winding 5, the transformer 1 can be used as a reactor.

[0030] As shown in FIG. 5, the insulating plates 4 and 6 have through holes for surrounding the middle leg portion 11a. The insulating plate 4 has a central hole 4a as a through hole, and the insulating plate 6 has a central hole 6a as a through hole. The insulating plates 4 and 6 are formed into plate shapes by molding with an insulating resin material such as epoxy resin. As shown in FIG. 8, the insulating plate 4 has a first groove portion 4b for positioning the primary winding 3. As shown in FIG. 9, the insulating plate 6 has a second groove portion 6b for positioning the secondary winding 5. As shown in FIG. 10, when forming the coil body 2, the primary winding 3 is fitted into the first groove portion 4b. As shown in FIG. 11, when forming the coil body 2, the secondary winding 5 is fitted into the second groove portion 6b.

[0031] As shown in FIG. 12, the cooling plate 7 has a main body portion 71 which is a portion overlapping the winding, and a first cooling portion 72 and a second cooling portion 73 protruding from the main body portion 71. As shown in FIG. 14, each of the first cooling portion 72 and the second cooling portion 73 is at least thermally connected to a housing 9 which is a cooler. In the present embodiment, as shown in FIG. 12, the first cooling portion 72 has a first fixing portion 72a which is a portion fixed to the housing 9 of the first cooling portion 72, an extending portion 72b which is a portion extending in the direction of the housing 9, and a bending portion 72c which extends the extending portion 72b in the direction of the housing 9. Similarly, the second cooling portion 73 has a second fixing portion 73a which is a portion fixed to the housing 9 of the second cooling portion 73, an extending portion 73b which is a portion extending in the direction of the housing 9, and a bending portion 73c which extends the extending portion 73b in the direction of the housing 9. The bending portion 72c and the bending portion 73c are exposed from the molding resin 8.

[0032] The main body portion 71 overlapping the winding is thermally connected to the winding. The first fixing portion 72a is fixed to the cooling surface 9a, and the second fixing portion 73a is fixed to the cooling surface 9a. The method of fixing the first fixing portion 72a and the second fixing portion 73a to the cooling surface 9a is, for example, screwing. By configuring in this way, the heat generated in the winding can be transmitted to the housing 9 through the cooling plate 7, so that the heat dissipation characteristics of the transformer 1 can be improved.

[0033] The cooling plate 7 is made of a metal such as aluminum or copper. A central hole 7a, which is a through-hole for surrounding the middle leg portion 11a, is provided at the center of the main body portion 71. The main body portion 71 is a portion shown by a broken-line quadrilateral having four vertices 71a, 71b, 71c, and 71d. The main body portion 71 is formed in a plate shape parallel to the XY plane. A line segment 712 connecting the vertex 71b and the vertex 71c and a line segment 714 connecting the vertex 71a and the vertex 71d are parallel to the Y direction and face each other outside the window portions 12a and 12b of the magnetic core 12. The line segment 714 is arranged on the outer leg portion 11b side when viewed from the middle leg portion 11a, and the line segment 712 is arranged on the outer leg portion 11c side when viewed from the middle leg portion 11a. Also, a line segment 711 connecting the vertex 71a and the vertex 71b and a line segment 713 connecting the vertex 71c and the vertex 71d are parallel to the X direction and face each other with the window portions 12a and 12b of the magnetic core 12 interposed therebetween.

[0034] In the present embodiment, the main body portion 71 of the cooling plate 7 has cutting portions 71e and 71f provided parallel to the X direction. The cutting portion 71e divides the portion of the main body portion 71 between the middle leg portion 11a and the outer leg portion 11b in the Y direction. The cutting portion 71f divides the portion of the main body portion 71 between the middle leg portion 11a and the outer leg portion 11c in the Y direction. When viewed in the Z direction, the cutting portion 71e is arranged to overlap with the window portion 12a, and the cutting portion 71f is arranged to overlap with the window portion 12b.

[0035] When a current flows through the primary winding 3 or the secondary winding 5, a magnetic field is generated inside the magnetic core 12, and magnetic flux links with the portion of the central hole 7a of the cooling plate 7, so that an induced current that circulates around the middle leg portion 11a is generated in the main body portion 71 of the cooling plate 7. By providing at least one of the cutting portions 71e and 71f, it is possible to prevent an induced current, so-called one-turn short. In the present embodiment, since the cutting portions 71e and 71f are portions provided as insulating portions described later, both of the cutting portions 71e and 71f are provided.

[0036] In the present embodiment, as described above, the magnetic core 12 is thermally connected to the cooling surface 9a, and each of the first cooling unit 72 and the second cooling unit 73 has a portion extending in the direction of the cooling surface 9a, and the first cooling unit 72 and the second cooling unit 73 are thermally connected to the cooling surface 9a. By configuring in this way, since the first cooling unit 72 and the second cooling unit 73 are arranged adjacent to the magnetic core 12 thermally connected to the cooling surface 9a, the transformer 1 can be miniaturized. Further, since the heat dissipation path by the first cooling unit 72 and the second cooling unit 73 is shortened, the heat dissipation characteristics of the transformer 1 can be improved.

[0037] <Comparative Example> Prior to the description of the arrangement of the first cooling unit 72 and the second cooling unit 73, which are the main parts of the present disclosure, and the insulating part, a comparative example will be described with reference to FIGS. 17 to 19. FIG. 17 is a perspective view showing a cooling plate 20 of a transformer 1a of the comparative example, FIG. 18 is a plan view showing an outline of a power converter 200a of the comparative example, showing the magnetic core 12, the cooling plate 20, and its surroundings, and FIG. 19 is a cross-sectional view of the power converter 200a of the comparative example cut at the B-B cross-sectional position (a cross-sectional position parallel to the X direction) of FIG. 18, showing only the magnetic core 12. The transformer 1a of the comparative example is obtained by replacing the cooling plate 7 of the transformer 1 with the cooling plate 20. Since the configuration other than the cooling plate 20 is the same as that of the transformer 1, the same reference numerals are used for other constituent members. Hereinafter, the magnetic flux distribution in the magnetic core 12 during the operation of the transformer 1a of the comparative example will be described.

[0038] First, the cooling plate 20 will be described. As shown in FIG. 17, the cooling plate 20 has a main body portion 21 which is a portion overlapping the winding, and a first cooling portion 22 and a second cooling portion 23 protruding from the main body portion 21. As shown in FIG. 18, each of the first cooling portion 22 and the second cooling portion 23 is thermally connected to the housing 9. In the comparative example, as shown in FIG. 17, the first cooling portion 22 has a first fixing portion 22a which is a portion fixed to the housing 9 of the first cooling portion 22, an extending portion 22b which is a portion extending in the direction of the housing 9, and a bending portion 22c which extends the extending portion 22b in the direction of the housing 9. Similarly, the second cooling portion 23 has a second fixing portion 23a which is a portion fixed to the housing 9 of the second cooling portion 23, an extending portion 23b which is a portion extending in the direction of the housing 9, and a bending portion 23c which extends the extending portion 73b in the direction of the housing 9.

[0039] The cooling plate 20 is made of a metal such as aluminum or copper. A central hole 20a, which is a through hole for surrounding the middle leg portion 11a, is provided at the center of the main body portion 71. The main body portion 21 is a portion shown by a broken-line quadrilateral having four vertices 21a, 21b, 21c, and 21d. The main body portion 21 is formed in a plate shape parallel to the XY plane. A line segment 212 connecting the vertex 21b and the vertex 21c and a line segment 214 connecting the vertex 21a and the vertex 21d are parallel to the Y direction and face each other outside the window portions 12a and 12b of the magnetic core 12. The line segment 214 is arranged on the side of the outer leg portion 11b when viewed from the middle leg portion 11a, and the line segment 212 is arranged on the side of the outer leg portion 11c when viewed from the middle leg portion 11a. Also, a line segment 211 connecting the vertex 21a and the vertex 21b and a line segment 213 connecting the vertex 21c and the vertex 21d are parallel to the X direction and face each other with the window portions 12a and 12b of the magnetic core 12 interposed therebetween. In order to prevent an induced current circulating around the middle leg portion 11a from being generated in the main body portion 21, a cutting portion 21e is formed in the main body portion 21. In the comparative example, the cutting portion 21e is provided at a position parallel to the Y direction and overlapping the midpoint 211a of the line segment 211.

[0040] Describe the magnetic flux distribution in the magnetic core 12 when current flows through the primary winding 3 of the transformer 1a. The magnetic flux when current flows from the terminal portion 3b to the terminal portion 3c of the primary winding 3 is shown by dashed arrows superposed on the closed magnetic paths 101 and 102 in FIG. 19. A magnetic flux 31 is generated in the counterclockwise direction in the closed magnetic path 101, and a magnetic flux 32 is generated in the clockwise direction in the closed magnetic path 102. At this time, as shown in FIG. 18, a current loop 90a is formed in a path surrounding the outer leg portion 11b of the magnetic core 12 by the main body portion 21, the first cooling portion 22, the housing 9, and the second cooling portion 23. In FIG. 18, the outer leg portion 11b is shown by hatching. Since the magnetic flux 31 passing through the middle leg portion 11a links with the current loop 90a, according to Lenz's law, a current flows in the counterclockwise direction as viewed from the Z direction in the current loop 90a. Therefore, a magnetic flux 33 is generated in the clockwise direction shown by the solid arrow in FIG. 19 in the closed magnetic path 101 of the magnetic core 12. Note that a part of the magnetic flux 33 links with the outer leg portion 11c, but it is omitted for simplicity of explanation.

[0041] As shown in FIG. 19, since a part of the magnetic flux 31 generated by the current flowing through the primary winding 3 is canceled by the magnetic flux 33 generated by the current loop 90a, the magnetic flux linking with the secondary winding 5 decreases, so a part of the power of the primary winding 3 is not transmitted to the secondary winding 5. That is, similar to the description of the problem in Patent Document 1, when the cooling plate 20 is provided to improve the heat dissipation characteristics of the transformer 1a shown in the comparative example, the magnetic flux 31 generated by the current flowing through the primary winding 3 decreases, so a part of the power of the primary winding 3 is not transmitted to the secondary winding 5, and thus the function of the transformer 1a deteriorates.

[0042] <Arrangement of the First Cooling Portion 72 and the Second Cooling Portion 73 and the Insulating Portion> The arrangement of the first cooling unit 72 and the second cooling unit 73, which are the main parts of the present disclosure, and the insulating part will be described. As shown in FIG. 12, each of the first cooling unit 72 and the second cooling unit 73 protrudes from each of the portions of the main body 71 on both sides sandwiching the window portions 12a and 12b. In the present embodiment, the first cooling unit 72 and the second cooling unit 73 face each other in the Y direction, and the first cooling unit 72 and the second cooling unit 73 protrude from the other portion of the main body 71 in the X direction. The first cooling unit 72 is provided on the side of the vertex 71a of the main body 71, and the second cooling unit 73 is provided on the side of the vertex 71d of the main body 71. The path surrounding the magnetic core 12 by the main body 71, the first cooling unit 72, the housing 9, and the second cooling unit 73 has at least one insulating part, and the path is electrically insulated by the insulating part. In the present embodiment, the insulating parts are the cut portions 71e and 71f of the main body 71 that cut between the main bodies 71 on both sides sandwiching the window portions 12a and 12b. In the present embodiment, the portion of the magnetic core 12 surrounded by the path is the outer leg portion 11b.

[0043] The distribution of the magnetic flux in the magnetic core 12 when a current is passed from the terminal portion 3b to the terminal portion 3c of the primary winding 3 shown in FIG. 6 will be described. The magnetic flux when the current is passed is shown in FIG. 15 by broken-line arrows superposed on the closed magnetic paths 101 and 102. Due to the current flowing through the primary winding 3, magnetic fluxes flowing from the middle leg portion 11a toward the outer leg portions 11b and 11c are generated. A magnetic flux 14 is generated in the closed magnetic path 101 in the counterclockwise direction, and a magnetic flux 15 is generated in the closed magnetic path 102 in the clockwise direction. At this time, as shown in FIG. 16, when there are no cut portions 71e and 71f, a current loop 90 is formed in the path surrounding the magnetic core 12 by the main body 21, the first cooling unit 22, the housing 9, and the second cooling unit 23. However, since the cut portions 71e and 71f are provided, the current loop 90 is cut, so the current loop 90 is not formed. Since the current loop 90 is not formed, different from the transformer 1a of the comparative example, it is possible to prevent the current flowing through the current loop 90a of the comparative example and the generation of the magnetic flux 33 caused by the current loop 90a.

[0044] Since the generation of the magnetic flux 33 due to the current loop 90a is suppressed, the magnetic flux 14 generated by the current flowing through the primary winding 3 does not decrease. Therefore, the power of the primary winding 3 can be transmitted to the secondary winding 5 without impairing the power of the primary winding 3. Unlike the transformer 1a of the comparative example, the transformer 1 can transmit the power of the primary winding 3 to the secondary winding 5 without impairing the power of the primary winding 3 even if the cooling plate 7 is provided to improve the heat dissipation characteristics. Since the power of the primary winding 3 can be transmitted to the secondary winding 5 without being impaired, a transformer 1 having high heat dissipation characteristics and a power converter 200 using the same can be obtained without degrading the function of the transformer 1. Since the transformer 1 has high heat dissipation characteristics, the transformer 1 can be miniaturized. Since the transformer 1 is miniaturized, the cost of the transformer 1 can be reduced.

[0045] In the present embodiment, the cutting portions 71e and 71f are provided as the insulating portions. The configuration of the insulating portion is not limited to this. When the cutting portions 71e and 71f are provided as the insulating portions, the insulating portion can be provided in the main body portion 71, so that an additional insulating portion is not required, and the cost of the transformer 1 can be reduced. Further, since the insulating portion can be formed simultaneously with the manufacture of the cooling plate 7, the productivity of the transformer 1 can be improved.

[0046] Even when the secondary winding 5 is removed and the transformer 1 is used as a reactor, the decrease in the magnetic flux generated in the magnetic core 12 due to the current flowing through the primary winding 3 can be prevented in the same manner as in the transformer 1. Since the decrease in the magnetic flux generated in the magnetic core 12 can be prevented, the decrease in the L value of the reactor can be prevented. Therefore, a reactor having high heat dissipation characteristics can be obtained without degrading the function of the reactor.

[0047] In the present embodiment, the first cooling unit 72 and the second cooling unit 73 face each other in the Y direction, and the first cooling unit 72 and the second cooling unit 73 protrude from the other part of the main body 71 in the X direction. However, the arrangement of the first cooling unit 72 and the second cooling unit 73 is not limited to this. The arrangement of the first cooling unit 72 and the second cooling unit 73 in the present embodiment was to cut off the current loop formed around the outer leg portion 11b. The first cooling unit 72 and the second cooling unit 73 may be arranged on one side and the other side in the Y direction of the main body 71, respectively, and may be configured to cut off the current loop formed around the beam portion 11d.

[0048] <Modification Example> A modification example of the transformer 1 provided with an insulating portion different from the cut portions 71e and 71f of the transformer 1 shown above will be described with reference to FIG. 20. FIG. 20 is a side view showing a main part of another transformer 1 according to Embodiment 1, and is a view showing the first cooling unit 72 and its surroundings from the other side in the X direction. In the modification example, the insulating portion is a heat radiating member 16 made of an insulating material provided between one or both of the first fixing portion 72a which is a portion fixed to the housing 9 of the first cooling unit 72 and the second fixing portion 73a which is a portion fixed to the housing 9 of the second cooling unit 73 and the housing 9.

[0049] The heat radiating member 16 is, for example, a heat transfer sheet such as a silicone rubber sheet or a urethane rubber sheet. Even if the heat radiating member 16 made of an insulating material is provided without providing the cut portions 71e and 71f, the current loop formed around the magnetic core 12 can be cut off. Since the insulating portion is the heat radiating member 16, the thermal resistance between the cooling plate 7 and the housing 9 is reduced, and the temperature rise of the winding can be further suppressed. Although FIG. 20 shows an example in which the heat radiating member 16 is provided between the first fixing portion 72a and the housing 9, the present invention is not limited to this, and the heat radiating member 16 may be provided between the second fixing portion 73a and the housing 9. Further, the heat radiating member 16 may be provided only between the second fixing portion 73a and the housing 9.

[0050] When cutting the current loop with a heat dissipation member 16 made of an insulating material instead of the cutting portion, since it is not necessary to provide the cutting portions 71e and 71f in the main body portion 71, the area of the main body portion 71 is enlarged, so that the heat dissipation characteristics of the transformer 1 by the cooling plate 7 can be improved. Hereinafter, the details of improving the heat dissipation characteristics of the transformer 1 will be described.

[0051] The magnetic core 12 of the transformer 1 generates heat because iron loss occurs during operation. Therefore, in the transformer 1 having the cutting portions 71e and 71f, when viewed from the Z direction, the portions of the primary winding 3 and the secondary winding 5 arranged at the locations overlapping the cutting portions 71e and 71f are affected by the heat generation of the magnetic core 12 through the cutting portions 71e and 71f, so the temperature rises. Also, at the locations where the cutting portions 71e and 71f are arranged, when viewed from the Z direction, since there is no cooling plate 7 with excellent heat dissipation characteristics, the primary winding 3 and the secondary winding 5 cannot be cooled by the cooling plate 7, so the temperature of the primary winding 3 and the secondary winding 5 further increases. On the other hand, in the configuration where the current loop is cut by the heat dissipation member 16, the cutting portions 71e and 71f are not provided. Therefore, in the configuration where the current loop is cut by the heat dissipation member 16, when viewed from the Z direction, the portions of the primary winding 3 and the secondary winding 5 and the magnetic core 12 do not face each other, and since the cooling plate 7 is arranged between the primary winding 3 and the secondary winding 5 and the magnetic core 12, the primary winding 3 and the secondary winding 5 are cooled by the cooling plate 7, so the heat dissipation characteristics of the transformer 1 are improved.

[0052] As described above, in the transformer 1 according to the first embodiment, there are a magnetic core 12 having an annular portion surrounding the window portions 12a and 12b, one or a plurality of windings wound around the annular portion of the magnetic core 12, and a cooling plate 7 that penetrates the window portions 12a and 12b, is provided overlapping the windings, is made of metal, and cools the windings. The cooling plate 7 has a main body portion 71 that is a portion overlapping the windings, and a first cooling portion 72 and a second cooling portion 73 that protrude from the main body portion 71. Each of the first cooling portion 72 and the second cooling portion 73 is at least thermally connected to the housing 9. Each of the first cooling portion 72 and the second cooling portion 73 protrudes from each of the portions of the main body portion 71 on both sides sandwiching the window portions 12a and 12b. The path surrounding the magnetic core 12 by the main body portion 71, the first cooling portion 72, the housing 9, and the second cooling portion 73 has at least one insulating portion, and since the path is electrically insulated by the insulating portion, the generation of current flowing through the path and magnetic flux caused by the flowing current is suppressed, and the magnetic flux generated by the current flowing through the windings does not decrease. Therefore, a transformer 1 having high heat dissipation characteristics by the cooling plate 7 and a power converter 200 using the same can be obtained without degrading the function of the transformer 1. Since the transformer 1 has high heat dissipation characteristics, the transformer 1 can be miniaturized. Since the transformer 1 is miniaturized, the cost of the transformer 1 can be reduced.

[0053] When the insulating portions are the cutting portions 71e and 71f of the main body portion 71 that cut between the portions of the main body portion 71 on both sides sandwiching the window portions 12a and 12b, an insulating portion can be provided in the main body portion 71, so an additional insulating portion is not required, and the cost of the transformer 1 can be reduced. Also, since the insulating portion can be formed simultaneously with the manufacture of the cooling plate 7, the productivity of the transformer 1 can be improved.

[0054] When the insulating portion is a heat radiating member 16 made of an insulating material provided between one or both of a first fixing portion 72a that is a portion of the first cooling portion 72 fixed to the housing 9 and a second fixing portion 73a that is a portion of the second cooling portion 73 fixed to the housing 9 and the housing 9, it is not necessary to provide the cutting portions 71e and 71f in the main body portion 71, so the area of the main body portion 71 is enlarged, and the heat dissipation characteristics of the transformer 1 by the cooling plate 7 can be improved.

[0055] When the winding is formed in a plate shape that is curved on a plane and wound around the magnetic core 12 in an annular or spiral shape, by forming the winding in a plate shape, unlike the case where the winding is a round wire or the like, the mutually facing surfaces between the primary winding 3 and the secondary winding 5 via the insulating plate 6, and between the secondary winding 5 and the cooling plate 7 can be increased. Since the mutually facing surfaces between the respective windings and between the secondary winding 5 and the cooling plate 7 increase, the thermal resistance between them is reduced, so that the cooling effect of each winding can be improved. Since the cooling effect of each winding is improved, the transformer 1 and the power converter 200 can be miniaturized and cost-reduced.

[0056] In the power converter 200 according to the first embodiment, it includes the disclosed magnetic component and a housing 9 which is a cooler having a cooling surface 9a thermally connected to the magnetic core 12. Each of the first cooling part 72 and the second cooling part 73 has a portion extending in the direction of the cooling surface 9a. Since the first cooling part 72 and the second cooling part 73 are thermally connected to the cooling surface 9a, the first cooling part 72 and the second cooling part 73 are arranged adjacent to the magnetic core 12 thermally connected to the cooling surface 9a, so that the transformer 1 can be miniaturized. Also, since the heat dissipation path by the first cooling part 72 and the second cooling part 73 is shortened, the heat dissipation characteristics of the transformer 1 can be improved.

[0057] Embodiment 2. The transformer 1 according to the second embodiment will be described. FIG. 21 is a plan view showing the cooling plate 40 of the transformer 1 according to the second embodiment. The transformer 1 according to the second embodiment has a configuration in which a cooling plate 40 is provided instead of the cooling plate 7 shown in FIG. 12 of the first embodiment.

[0058] The cooling plate 40 of the present embodiment will be described. In FIG. 21, the window portions 12a and 12b are provided at the positions indicated by the dashed lines. The main body portion 71 is provided at the portions of the window portions 12a and 12b and on both sides sandwiching the window portions 12a and 12b. Both the first cooling portion 72 and the second cooling portion 73 protrude from the portion of the main body portion 71 on one side sandwiching the window portions 12a and 12b and do not protrude to the main body portion 71 on the other side sandwiching the window portions 12a and 12b. In the cooling plate 7 shown in the first embodiment, the second cooling portion 73 is provided on one side in the Y direction with the window portions 12a and 12b sandwiching the first cooling portion 72, but in the cooling plate 40, the second cooling portion 73 is provided on the side of the vertex 71b of the main body portion 71 that does not sandwich the window portions 12a and 12b with respect to the first cooling portion 72. Also, the cutting portion 71e provided in the cooling plate 7 is not provided in the cooling plate 40. The cutting portion 71f is provided to prevent a one-turn short circuit.

[0059] By configuring in this way, since no current loop is formed in the path surrounding the magnetic core 12 by the main body portion 71, the first cooling portion 22, the housing 9, and the second cooling portion 23, it is possible to prevent the generation of the magnetic flux 33 caused by the current loop. Since the generation of the magnetic flux caused by the current loop is suppressed, the magnetic flux 14 generated by the current flowing through the primary winding 3 does not decrease, so the power of the primary winding 3 can be transmitted to the secondary winding 5 without impairing the power of the primary winding 3. Even if the cooling plate 40 is provided to improve the heat dissipation characteristics, the transformer 1 can transmit the power of the primary winding 3 to the secondary winding 5 without impairing the power of the primary winding 3. Since the power of the primary winding 3 can be transmitted to the secondary winding 5 without impairment, it is possible to obtain a transformer 1 having high heat dissipation characteristics and a power converter 200 using the same without degrading the function of the transformer 1.

[0060] Further, unlike the cooling plate 7, the cooling plate 40 does not require the cutting portion 71e. Therefore, since the area reduction of the main body portion 71 of the cooling plate 40 due to the formation of the cutting portion 71e does not occur, it is possible to suppress a decrease in the heat radiation characteristics of the transformer 1. Since the decrease in the heat radiation characteristics of the transformer 1 is suppressed, the components constituting the transformer 1 can be miniaturized. Furthermore, since the cooling plate 40 does not require the heat radiation member 16 provided between one or both of the first fixing portion 72a of the first cooling portion 72 and the second fixing portion 73a of the second cooling portion 73 and the housing 9, the cost of the transformer 1 can be reduced.

[0061] Embodiment 3. The transformer 1 according to Embodiment 3 will be described. FIG. 22 is a plan view showing the cooling plate 50 of the transformer 1 according to Embodiment 3, and is a view in which the outer shape of the secondary winding 5 arranged to overlap the cooling plate 50 is indicated by a one-dot chain line. FIG. 23 is a cross-sectional view showing a main part of the transformer 1, and is a view of the coil body 2 in the X direction. The transformer 1 according to Embodiment 3 has a configuration in which a cooling plate 50 is provided instead of the cooling plate 7 shown in FIG. 12 of Embodiment 1.

[0062] In FIG. 22, a portion provided on the other side in the Y direction of the main body portion 71 divided by the cutting portions 71e and 71f is defined as a divided portion 71g, and a portion provided on one side in the Y direction of the main body portion 71 is defined as a divided portion 71h. The outer shape of the main body portion 71 is indicated by a broken line. In the present embodiment, the cutting portion 71e is provided parallel to the X direction passing through the midpoint of the line segment 714, and the cutting portion 71f is provided parallel to the X direction passing through the midpoint of the line segment 712. Only the outer shape of the secondary winding 5 is shown in FIG. 22, but when viewed in the Z direction, the outer shape of the primary winding 3 and the outer shape of the secondary winding 5 coincide with each other.

[0063] In the path surrounding the magnetic core 12 by the main body portion 71, the first cooling portion 72, the housing 9, and the second cooling portion 73, the length from the cutting portion 71e to the first fixing portion 72a which is the portion fixed to the housing 9 of the first cooling portion 72, and the length from the cutting portion 71e to the second fixing portion 73a which is the portion fixed to the housing 9 of the second cooling portion 73 are equal. Similarly, the length from the cutting portion 71f to the first fixing portion 72a of the first cooling portion 72 and the length from the cutting portion 71f to the second fixing portion 73a of the second cooling portion 73 are equal. Being equal means that the designed lengths are the same, the difference in length is on the order of the tolerance, and there is a difference in length within the range of manufacturing error.

[0064] Prior to the explanation of the effects of the configuration shown in FIG. 22, a comparative example will be described with reference to FIG. 24. FIG. 24 is a plan view showing the cooling plate 60 of the comparative example. The cooling plate 60 has a configuration in which both of the cutting portions 71e and 71f of the cooling plate 50 are moved by the same distance to the other side in the Y direction, and the cutting portions after the movement are referred to as cutting portions 71i and 71j. A portion provided on the other side in the Y direction of the main body portion 71 divided by the cutting portions 71i and 71j is defined as a divided portion 71k, and a portion provided on one side in the Y direction of the main body portion 71 is defined as a divided portion 71l. The outer shape of the main body portion 71 is indicated by a dashed line. For simplicity of explanation, the reference numerals of the other configurations excluding the cutting portions and the divided portions are the same in FIGS. 22 and 24.

[0065] In the configuration of the comparative example, the length from the cutting portion 71i to the first fixing portion 72a of the first cooling portion 72 and the length from the cutting portion 71i to the second fixing portion 73a of the second cooling portion 73 are not equal, and the length from the cutting portion 71i to the first fixing portion 72a is small. Similarly, the length from the cutting portion 71j to the first fixing portion 72a of the first cooling portion 72 and the length from the cutting portion 71j to the second fixing portion 73a of the second cooling portion 73 are not equal, and the length from the cutting portion 71j to the first fixing portion 72a of the first cooling portion 72 is small. Therefore, when viewed in the Z direction, the area of the dividing portion 71l is larger than the area of the dividing portion 71k. Since the area of the dividing portion 71l is larger than the area of the dividing portion 71k, the heat transferred from the winding of the dividing portion 71l is larger than the heat transferred from the winding of the dividing portion 71k. Since only one fixing portion that is thermally connected to the housing 9 exists for both of the dividing portions 71k and 71l, the temperature of the winding on the side of the dividing portion 71l where a large amount of heat is transferred becomes higher than the temperature of the winding on the side of the dividing portion 71k. As shown in FIG. 24, when the lengths from the cutting portion to the fixing portion that is thermally connected to the housing 9 are not equal, the heat of the winding on the side where the length from the cutting portion to the fixing portion that is thermally connected to the housing 9 is long is less likely to be radiated through the cooling plate 60, so the temperature of the winding will increase.

[0066] As shown in FIG. 22, when the length from the cutting portion 71e to the first fixing portion 72a and the length from the cutting portion 71e to the second fixing portion 73a are equal, and the length from the cutting portion 71f to the first fixing portion 72a and the length from the cutting portion 71f to the second fixing portion 73a are equal, when viewed in the Z direction, the area of the dividing portion 71g and the area of the dividing portion 71h are equal. Therefore, since the heat transferred from the winding overlapping the dividing portion 71g to the dividing portion 71g and the heat transferred from the winding overlapping the dividing portion 71h to the dividing portion 71h are equal, the temperature of the winding on the side of one dividing portion does not become high. Since the temperature of the winding on the side of one dividing portion does not become high, the maximum temperature of the winding is suppressed, so the transformer 1 can be miniaturized.

[0067] In this embodiment, the length from the cutting portion 71e to the first fixing portion 72a is equal to the length from the cutting portion 71e to the second fixing portion 73a, and the length from the cutting portion 71f to the first fixing portion 72a is equal to the length from the cutting portion 71f to the second fixing portion 73a. By arranging each fixing portion at an equal distance from either of the two cutting portions 71e and 71f in this way, the effect of suppressing the maximum temperature of the winding is increased.

[0068] In this embodiment, the cooling plate 50 is arranged parallel to the winding, and when viewed in the direction of the winding center axis of the winding, the projected area of the main body portion 71 of the cooling plate 50 is equal to or larger than the projected area of the winding. As shown in FIG. 23, the cooling plate 50 is arranged parallel to the primary winding 3 and the secondary winding 5. As shown in FIG. 22, when viewed in the Z direction which is the direction of the winding center axis of the winding, the projected area of the main body portion 71 is larger than the projected areas of the primary winding 3 and the secondary winding 5. The projected area of the main body portion 71 is not limited to this, and the projected areas of the primary winding 3 and the secondary winding 5 and the projected area of the main body portion 71 may be equal.

[0069] By configuring in this way, since the primary winding 3 and the secondary winding 5 are arranged directly below the cooling plate 50, the distance between each location of the primary winding 3 and the secondary winding 5 and the cooling plate 50 is minimized, so that the transformer 1 can obtain high heat dissipation characteristics. Further, since the transformer 1 can obtain high heat dissipation characteristics, the components of the transformer 1 can be miniaturized. Since the components of the transformer 1 are miniaturized, the cost of the transformer 1 can be reduced.

[0070] Although various exemplary embodiments and examples are described in the present disclosure, the various features, aspects, and functions described in one or more embodiments are not limited to the application of a specific embodiment, but are applicable to the embodiments alone or in various combinations. Accordingly, countless variations not illustrated are envisioned within the scope of the technology disclosed in this specification. For example, it is assumed to include cases where at least one component is modified, added, or omitted, and further cases where at least one component is extracted and combined with components of other embodiments.

[0071] Hereinafter, aspects of the present disclosure will be collectively described as appendices. (Appendix 1) A magnetic core having an annular portion surrounding a window portion, One or more windings wound around the annular portion of the magnetic core, A cooling plate that penetrates the window portion, is provided overlapping the winding, is made of metal, and cools the winding, The cooling plate has a main body portion that is a portion overlapping the winding, and a first cooling portion and a second cooling portion protruding from the main body portion, Each of the first cooling portion and the second cooling portion is at least thermally connected to a cooler, Each of the first cooling portion and the second cooling portion protrudes from each of the portions of the main body portion on both sides sandwiching the window portion, and the path surrounding the magnetic core by the main body portion, the first cooling portion, the cooler, and the second cooling portion has at least one insulating portion, and the path is an electrical component insulated by the insulating portion. (Appendix 2) A magnetic core having an annular portion surrounding a window portion, One or more windings wound around the annular portion of the magnetic core, A cooling plate that penetrates the window portion, is provided overlapping the winding, is made of metal, and cools the winding, The cooling plate has a main body portion that is a portion overlapping the winding, and a first cooling portion and a second cooling portion protruding from the main body portion, Each of the first cooling portion and the second cooling portion is at least thermally connected to a cooler, Both the first cooling portion and the second cooling portion protrude from the portion of the main body portion on one side sandwiching the window portion, and are magnetic components that do not protrude to the other side sandwiching the window portion. (Appendix 3) The insulating part is the magnetic component according to Appendix 1, which is the cutting part of the main body part that cuts between the main body parts on both sides sandwiching the window part. (Appendix 4) In the path, the length from the cutting part to the first fixing part which is the part fixed to the cooler of the first cooling part, and the length from the cutting part to the second fixing part which is the part fixed to the cooler of the second cooling part are equal. The magnetic component according to Appendix 3. (Appendix 5) The insulating part is a heat dissipation member made of an insulating material provided between one or both of the first fixing part which is the part fixed to the cooler of the first cooling part and the second fixing part which is the part fixed to the cooler of the second cooling part and the cooler. The magnetic component according to Appendix 1. (Appendix 6) The winding is formed in a plate shape curved on a plane and wound around the magnetic core in an annular or spiral shape. The magnetic component according to any one of Appendices 1 to 5. (Appendix 7) The cooling plate is arranged parallel to the winding, When viewed in the direction of the winding center axis of the winding, the projected area of the main body part of the cooling plate is equal to or larger than the projected area of the winding. The magnetic component according to any one of Appendices 1 to 6. (Appendix 8) The magnetic component according to any one of Appendices 1 to 7, A cooler having a cooling surface to which the magnetic core is thermally connected, and Each of the first cooling part and the second cooling part has a portion extending in the direction of the cooling surface, The first cooling part and the second cooling part are power converters thermally connected to the cooling surface.

Explanation of Signs

[0072] 1. 1a transformer, 2 coil body, 2a central hole, 3 primary winding, 3a central hole, 3b, 3c terminal parts, 4 insulating plate, 4a central hole, 4b first groove part, 5 secondary winding, 5a central hole, 5b, 5c terminal parts, 6 insulating plate, 6a central hole, 6b second groove part, 7 cooling plate, 7a central hole, 71 body part, 71a, 71b, 71c, 71d vertices, 711, 712, 713, 714 line segments, 71e, 71f cut parts, 71g, 71h divided parts, 71i, 71j cut parts, 71k, 71l divided parts, 72 first cooling part, 72a first fixing part, 72b extending part, 72c bending part, 73 second cooling part, 73a second fixing part, 73b extending part, 73c bending part, 8 molding resin, 9 housing, 9a cooling surface, 10 I-shaped core, 10a beam part, 11 E-shaped core, 11a middle leg part, 11b, 11c outer leg parts, 11d beam part, 12 magnetic core, 12a, 12b window parts, 13 adhesive tape, 14, 15 magnetic fluxes, 16 heat dissipation member, 20 cooling plate, 20a central hole, 21 body part, 21a, 21b, 21c, 21d vertices, 211, 212, 213, 214 line segments, 211a midpoint, 21e cut part, 22 first cooling part, 22a first fixing part, 22b extending part, 22c bending part, 23 second cooling part, 23a second fixing part, 23b extending part, 23c bending part, 31, 32, 33 magnetic fluxes, 40 cooling plate, 50 cooling plate, 60 cooling plate, 90, 90a current loop, 101, 102 closed magnetic circuit, 200, 200a power converter

Claims

1. A magnetic core having an annular portion surrounding a window portion, One or more windings wound around the annular portion of the magnetic core, A cooling plate that penetrates the window portion, is provided overlapping the winding, is made of metal, and cools the winding, and The cooling plate has a main body portion that is a portion overlapping the winding, and a first cooling portion and a second cooling portion protruding from the main body portion, Each of the first cooling portion and the second cooling portion is at least thermally connected to a cooler, Each of the first cooling portion and the second cooling portion protrudes from each of the portions of the main body portion on both sides sandwiching the window portion, and the path surrounding the magnetic core by the main body portion, the first cooling portion, the cooler, and the second cooling portion has at least one insulating portion, and the path is a magnetic component that is electrically insulated by the insulating portion.

2. A magnetic core having an annular portion surrounding a window portion, One or more windings wound around the annular portion of the magnetic core, A cooling plate that penetrates the window portion, is provided overlapping the winding, is made of metal, and cools the winding, and The cooling plate has a main body portion that is a portion overlapping the winding, and a first cooling portion and a second cooling portion protruding from the main body portion, Each of the first cooling portion and the second cooling portion is at least thermally connected to a cooler, Both the first cooling portion and the second cooling portion protrude from a portion of the main body portion on one side sandwiching the window portion, and do not protrude to the other side sandwiching the window portion, a magnetic component.

3. The magnetic component according to claim 1, wherein the insulating portion is a cut portion of the main body portion that cuts between the main body portions on both sides sandwiching the window portion.

4. The magnetic component according to claim 3, wherein the length from the cut portion to the first fixing portion, which is the portion fixed to the cooler of the first cooling portion, in the path is equal to the length from the cut portion to the second fixing portion, which is the portion fixed to the cooler of the second cooling portion.

5. The magnetic component according to claim 1, wherein the insulating portion is a heat radiating member made of an insulating material provided between one or both of the first fixing portion, which is the portion fixed to the cooler of the first cooling portion, and the second fixing portion, which is the portion fixed to the cooler of the second cooling portion, and the cooler.

6. The magnetic component according to any one of claims 1 to 5, wherein the winding is formed in a plate shape curved on a plane and wound around the magnetic core in an annular or spiral shape.

7. The cooling plate is arranged parallel to the winding, The magnetic component according to claim 6, wherein, when viewed in the direction of the winding center axis of the winding, the projected area of the main body portion of the cooling plate is equal to or larger than the projected area of the winding.

8. A magnetic component according to claim 1 or 2, and a cooler having a cooling surface thermally connected to the magnetic core, wherein each of the first cooling portion and the second cooling portion has a portion extending in the direction of the cooling surface, and the first cooling portion and the second cooling portion are power converters thermally connected to the cooling surface.

Images